ARCGATE The Arctic boundary has been observed over many years to better understand and monitor the exchanges between the Arctic Ocean and its neighboring oceans. The unique geometry of the Arctic—surrounded [...] Polarstern set sail from Tromsø to drift in the Arctic Ocean for a year—trapped in the ice. The goal of the MOSAiC expedition was to study the Arctic, the epicenter of global warming, more closely than… [...] Since the early 20th century hydrographic measurements have been carried out in the Arctic Ocean. Although today the Arctic is a hotspot of climate change, data sampling is still sparse due to the large sea